super mario 3d land

So, there's 2 sides of the coin; 2D and 3D, but with 3D Land and 3D World, it's sort of a middle ground, and I don't know if it's even right to call the 3D Adventures a 3D Mario, more it's own thing. If they aren't a part of 3D Mario, what category are they in? 2.5D? Do we start calling 3D...